Project Summary Core C establishes an infrastructure for rigorous methodologies to study the neurobiological heterogeneity in ASD by integrating genetic testing with neuroimaging (structural and functional MRI) and neurophysiology (EEG) across projects. Core C will be led by Drs. Geschwind and Jeste, who will jointly design the experiments for correlating genetic variation with core measures of neural function. Dr. Geschwind will take major responsibility for genetic data-generation while Dr. Jeste will oversee electrophysiology studies. Drs. Bookheimer and Dapretto will oversee MRI methods. Drs. Geschwind and Jeste will coordinate efforts within Core C, between Core C and Core B, and between Core C and Projects I-IV through regular monthly meetings. Informed by our experience and success in ACE-I and II, we will strengthen an infrastructure that will support acquisition and analysis of excellent quality genetics, EEG and MRI, and we will ensure optimal participant retention using techniques and approaches optimized for infants and children with ASD. The core will provide a shared and thus more efficient infrastructure for projects using genetic analyses (all Projects), EEG (Projects I, II, III, IV) and resting state, structural and functional MRI (Projects I, III, IV). Core C personnel will contribute their expertise in acquisition and analysis of these datasets, utilizing new techniques in connectivity analysis using graph theory and machine-learning approaches for understanding the heterogeneity in key domains in ASD, including baseline connectivity, sensorimotor function and social communication/language, consistent with the Center's central themes. By consolidating all services within the core we maximize efficiency and consistency in implementing these techniques across projects. Through this integrative process, we will begin to move the field towards a more biologically based classification, which in turn we expect to improve our clinical care by improving prognostication, treatment choice and outcomes.